Stibnut
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Drying formic acid with molecular sieves - CO risk?
I've got a very basic question. If I have 95% formic acid, and I want to make it anhydrous, would 4A molecular sieves be a good choice for drying?
The main reason I ask is that I don't want to accidentally evolve CO. Does anhydrous formic acid decompose much more rapidly than 95%, and is there
any chance that molecular sieves would catalyze this decomposition?
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Cryolite.
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You wouldn't form carbon monoxide, but you would destroy your sieves! Molecular sieves do not tolerate acid.
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PHILOU Zrealone
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And he will also contaminate his formic acid with soluble stuffs from the reaction of the molecular sieve with the acids...
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Stibnut
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D'oh! Okay, I won't try that.
What about MgSO4?
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Boffis
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Formic acid is up-graded by azeotropic distillation, usually with n-heptane or a petroleum ether with a close boiling range. The formic acid distils
over preferencially with the heptane. I have tried it but its not as easy as it sounds as a batch process because a lot of heptane distils for a small
amount of acid so you need a system to recycle the heptane continously and thats where it gets complex.
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